1. Field of the Invention
The present invention relates to an active cable.
2. Description of the Related Art
A cable with a connector, the cable including a cable provided with a plurality of differential signal transmission cables that are built therein and a connector provided at each of both ends of the cable, is used.
A paddle card that electrically connects a connection target device and the differential signal transmission cables to one another is built in the connector. A cable including a compensation circuit that actively compensates an electric signal in accordance with a loss property of the differential signal transmission cables and outputs the compensated electric signal to a transmission channel at a reception side in the paddle card, that is, a transmission channel through which an electric signal input from the differential signal transmission cable to the device, is also referred to as an active cable (an active direct-attach cable, an active DAC, or an active copper cable (ACC)).
As illustrated in FIGS. 4A and 4B, a known active cable 41 includes a cable 43 provided with a plurality of differential signal transmission cables 42, a connector 44 provided at each of both ends of the cable 43, and a paddle card 45 that is built in the connector 44 and electrically connects a connection target device (not illustrated) and the differential signal transmission cables 42 to one another. The active cable 41 is configured so as to be capable of performing single-channel transmission and reception, and includes one differential signal transmission cable 42 for each of transmission and reception, that is, two differential signal transmission cables 42 in total.
A plurality of transmission side electrodes 46 and a plurality of reception side electrodes 47, which are electrically connected to the device, are formed at one end portion of the paddle card 45. Also, a plurality of for-cable-connection transmission side electrodes 48 to which the differential signal transmission cables 42 for transmission are electrically connected and a plurality of for-cable-connection reception side electrodes 49 to which the differential signal transmission cables 42 for reception are connected are formed in the other end portion of the paddle card 45.
The transmission side electrodes 46 and the for-cable-connection transmission side electrodes 48 corresponding thereto are electrically connected to one another via a transmission side transmission channel 50. The reception side electrodes 47 and the for-cable-connection reception side electrodes 49 corresponding thereto are electrically connected to one another via a reception side transmission channel 51. A compensation circuit 52 that actively compensates an electric signal in accordance with a loss property of the differential signal transmission cables 42 and outputs the compensated electric signal is provided in the reception side transmission channel 51.
Ground layers 53 that are shared by a transmission side and a reception side are formed in an inner layer and a back layer (other layers than layers in which the transmission channels 50 and 51 are formed) of the paddle card 45.
In the known active cable 41, each of the transmission side transmission channel 50 and the reception side transmission channel 51 has a microstrip structure, and both of the transmission side transmission channel 50 and the reception side transmission channel 51 are formed in the same layer (a surface layer of the paddle card 45).
Note that, as relevant art document information related to the present invention, there is Japanese Unexamined Patent Application Publication No. 2013-122825.